The 39-year-old has quickly emerged as the leading candidate to replace Erik ten Hag, who was relieved of his duties as Red Devils manager on Monday after two-and-a-half years at Old Trafford.
Ten Hag only penned a new two-year contract in July and Man United's decision to now sack the Dutchman has been described as 'difficult and finely balanced' by the club's hierarchy.
However, 2-1 defeat at West Ham United in the Premier League last weekend proved to be the final nail in the coffin for Ten Hag, who has overseen just four wins in 14 games as Man United boss in all competitions this season.
The 54-year-old leaves the Red Devils languishing 14th in the Premier League table and also 21st in the 36-team Europa League standings, while Ruud van Nistelrooy has been placed in interim charge as "a permanent head coach is recruited" by Man United.
It is understood that Van Nistelrooy, who was brought to Man United as Ten Hag's number two in the summer, is reluctant to become the club's permanent manager as he does not want to 'stab his compatriot in the back'.
Sporting to name Pereira as Amorim' successor?
Man United have therefore stepped up their pursuit of Amorim and a recent report claims that the Sporting boss has agreed in principle to succeed Ten Hag, after accepting the club's project and the terms discussed.
According to Portuguese news outlet A Bola, Sporting will only let Amorim leave if Man United activate his €10m (£8.5m) release clause, which the Premier League club are willing to play.
The report adds that Amorim's imminent departure is 'so serious' that they already have a solution to replace their current head coach.
It is claimed that the reigning Primeira Liga champions have 'confirmed' their successor to Amorim and will name B team coach Joao Pereira as their new first-team manager.
Amorim talked up Pereira's credentials as a coach in May, telling reporters: "Joao Pereira is making his mark, I think he is an excellent coach. He has all the conditions to become Sporting's coach."
Pereira, who has been in charge of the B team since 2022-23, had three spells as a player at Sporting during his career and was part of the club's title-winning squad under Amorim in 2020-21.